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Discussion Starter · #1 ·
Hi. Thought I'd post this to see what advice the group has to provide. I've recently been given a relatively complete CB77 engine and rolling chassis. Sounds great right? Well condition is key and here's the condition: Bent frame/swing arm, good forks, good wheel hubs. Engine missing points cover, pistons seized, 1 rocker broken.

Upon getting the lump, I went through the bike essentially ditching the frame. Noticed the tappet cover had an indentation from the inside out. Pulled the tappet cover and discovered the rocker was broken (cant find the broken piece yet). The head was pulled immediately see crud in the engine...Pistons are stuck. They were soaked for days with Marvels and nada. Eventually, used a bit of force and was able to get the cylinders loose enough to be force ably yanked. Discovered cracks in the apron area of both sleeves. The transmission seems to click through the gears fine. Valve area will need some work as clearly they have been subject to moisture.

Before spending any money on the engine, I think I should split the case and see if that broken valve rocker made it's way into the bottom and did any further damage.

IF the bottom end looks good, do you think this engine would be worth salvaging? Side covers look great and are uncracked. My plan would be to pick up a frame and build a little hot resto mod if not too cost prohibitive.
 

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Take the lower end apart and see what it looks like then make a list of parts needed, see if you can locate parts and cost. Then add in the cost of having the sleeves replaced and bored for pistons. IMHO I would walk away from it. Look at e-bay , CMS, Ohio Cycle and Partzilla and [email protected]. Go to the Honda 305 site before spending any money.

Just some thoughts.

Bill
 

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Assuming that the bottom end looks ok, I would look at ebay for a set of used cylinders with pistons. They come up frequently, and are usually fairly reasonable in cost. If the head has no other damage, it is not a big project to replace a rocker. Frames with and without titles come up on ebay frequently.
 

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Discussion Starter · #4 ·
That's what I was thinking too. I have a CB160 that I'm putting new clutch plates in for road worthy shape. Once that's done, I'll tear down this '305 bottom end for further autopsy.

I've just located a CB77 frame on CL but it's missing the swingarm. Would be great to find something near Pittsburgh PA if poss.
 

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Discussion Starter · #5 ·
Pulled the lower end apart and could not find any foreign objects. No clue where that broken valve rocker arm ended up. Discovered the PO decided to weld the shifter arm to the spline. Had to grind the weld down then pull the arm. Looks like I'll need to pick up a used spline.

I should probably just scrap this build, as I really have few parts to work with...but I've been a sucker for old Honda's in the past. This will be the fourth that I've saved from the dumpster assuming I move forward.

Progress coming!
 

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Discussion Starter · #6 ·
The head is coming along nicely and will be finished up quick. However, I'm in need of serviceable cylinders. Any for sale here? Mine would require new sleeves at a cost of $200 plus installation. Not sure if it's worth buying the sleeves or not.
 

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305 cylinders are commonly available for reasonable prices on ebay. If you find a set at standard bore, you might get away with a hone job and new rings. If not, you could bore it out to one size larger. My local machine shop charges $40 a hole for boring. The down side to new sleeves is that they usually have to be bored after installation.
 
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